Drill bit assembly imaging systems and methods

ABSTRACT

Drill bit assembly imaging systems and methods are disclosed herein. An example method disclosed herein includes directing light conveying an image of a target through a portion of a drill bit assembly and capturing the image via an image sensor disposed inside the drill bit assembly. The example method also include determining drilling information based on the image via an image processor disposed inside the drill bit assembly.

FIELD OF THE DISCLOSURE

This disclosure relates generally to drilling applications and, moreparticularly, to drill bit assembly imaging systems and methods.

BACKGROUND

A downhole drilling tool is often used to drill boreholes to locateand/or produce hydrocarbons. During drilling, information related to asubterranean formation and/or fluids produced via the subterraneanformation may assist an operator of the downhole drilling tool. Forexample, the operator may adjust a trajectory and/or a speed of a drillbit of the downhole drilling tool based on a geological property of thesubterranean formation.

SUMMARY

This summary is provided to introduce a selection of concepts that arefurther described below in the detailed description. This summary is notintended to identify key or essential features of the claimed subjectmatter, nor is it intended to be used as an aid in limiting the scope ofthe claimed subject matter.

An example apparatus disclosed herein includes a drill bit assembly. Theexample apparatus also includes an image sensor and an image conduitdisposed in the drill bit assembly. The image conduit is to direct lightconveying an image to the image sensor. The example apparatus furtherincludes an image processor disposed in the drill bit assembly. Theimage processor is to process the image to determine information relatedto a target in the image.

An example method disclosed herein includes directing an image of atarget through a portion of a drill bit assembly and capturing the imagevia an image sensor disposed inside the drill bit assembly. The examplemethod also include determining drilling information based on the imagevia an image processor disposed inside the drill bit assembly.

Another example apparatus disclosed herein includes a drill bit assemblyoperatively coupled to a downhole tool. The drill bit assembly includesan image conduit, an image sensor and an image processor. The imagesensor is to capture an image of a target via the image conduit, and theimage processor is to determine target information based on the image.

BRIEF DESCRIPTION OF THE DRAWINGS

Example embodiments of example drill bit assembly imaging systems andmethods are described with reference to the following figures. The samenumbers are used throughout the figures to reference like features andcomponents.

FIG. 1 illustrates an example system in which example embodiments ofdrill bit assembly imaging systems and methods can be implemented;

FIG. 2 illustrates various components of a first example device that canimplement example embodiments of drill bit assembly imaging systems andmethods;

FIG. 3 illustrates various components of a second example device thatcan implement example embodiments of drill bit assembly imaging systemsand methods;

FIG. 4 illustrates various components of a third example device that canimplement example embodiments of drill bit assembly imaging systems andmethods;

FIG. 5 illustrates various components of a fourth example device thatcan implement example embodiments of drill bit assembly imaging systemsand methods;

FIG. 6 illustrates various components of a fifth example device that canimplement example embodiments of drill bit assembly imaging systems andmethods;

FIG. 7 illustrates example method(s) in accordance with one or moreembodiments.

FIG. 8 illustrates an example processor platform that may be used and/orprogrammed to implement at least some of the example methods andapparatus disclosed herein.

DETAILED DESCRIPTION

It is to be understood that the following disclosure provides manydifferent examples for implementing different features of variousembodiments. Specific examples of components and arrangements aredescribed below to simplify the present disclosure. These are, ofcourse, merely examples and are not intended to be limiting. Inaddition, the present disclosure may repeat reference numerals and/orletters in the various examples. This repetition is for the purpose ofsimplicity and clarity and does not in itself dictate a relationshipbetween the various examples and/or configurations discussed. Moreover,the formation of a first feature over or on a second feature in thedescription that follows may include examples in which the first andsecond features are formed in direct contact, and may also includeexamples in which additional features may be formed interposing thefirst and second features such that the first and second features maynot be in direct contact.

Drill bit assembly imaging systems and methods are disclosed herein. Anexample drill bit assembly includes a drill bit and an extension. Theextension operatively couples the drill bit to a downhole tool. Anexample imaging system disclosed herein is disposed in the example drillbit assembly to capture images of targets inside and/or outside thedrill bit assembly and to process the images downhole in the drill bitassembly during drilling. For example, the imaging system may determinetarget information. Target information is information related to one ormore targets in one or more of the images. In some examples, the targetinformation includes a size, a trajectory, a color, a texture, a shape,and/or any other information related to the target(s). In some examples,based on the target information, the imaging system determines drillinginformation. Drilling information is information related to a drillingoperation. Drilling information may include, for example, a state and/orcondition of a component of the drill bit assembly, penetration of a gaszone by the drill bit, a change in a geological property of asubterranean formation through which the drill bit assembly is drilling,and/or any other information related to the drilling operation. Byprocessing the images downhole, the target information and/or thedrilling information may be communicated uphole to a receiver in realtime via a low bandwidth, wireless telemetry link.

The example imaging system may include an example image conduit inoptical communication with an example image sensor. In some examples,the image sensor captures images at a high frame rate such as, forexample, a frame rate of about 1000 frames per second. The exampleimaging system may also include an example image processor disposed inthe drill bit assembly to process the images captured by the imagesensor. In some examples, the image processor combines a plurality ofimages captured by the image sensor to generate one or more processedimages having less or substantially no blur relative to the imagescaptured by the image sensor. Based on the processed image(s), the imageprocessor may determine the target information and/or the drillinginformation.

FIG. 1 illustrates an example wellsite system in which the examplesdisclosed herein can be employed. The wellsite can be onshore oroffshore. In this example system, a borehole 11 is formed in subsurfaceformations by rotary drilling in any appropriate manner. Examples canalso use directional drilling, as will be described hereinafter.

A drill string 12 is suspended within the borehole 11 and has a bottomhole assembly 100 which includes a drill bit 105 at its lower end. Thesurface system includes platform and derrick assembly 10 positioned overthe borehole or wellbore 11, the assembly 10 including a rotary table16, a kelly 17, a hook 18 and a rotary swivel 19. The drill string 12 isrotated by the rotary table 16, energized by means not shown, whichengages the kelly 17 at the upper end of the drill string 12. The drillstring 12 is suspended from the hook 18, attached to a traveling block(also not shown), through the kelly 17 and the rotary swivel 19, whichpermits rotation of the drill string 12 relative to the hook 18. In someexamples, a top drive system could be used.

In the illustrated example, the surface system further includes drillingfluid or mud 26 stored in a pit 27 formed at the well site. A pump 29delivers the drilling fluid 26 to the interior of the drill string 12via a port in the swivel 19, causing the drilling fluid 26 to flowdownwardly through the drill string 12 as indicated by the directionalarrow 8. The drilling fluid 26 exits the drill string 12 via ports inthe drill bit 105, and then circulates upwardly through the annulusregion between the outside of the drill string 12 and the wall of theborehole 11, as indicated by the directional arrows 9. In this manner,the drilling fluid 26 lubricates the drill bit 105 and carries formationcuttings up to the surface as it is returned to the pit 27 forrecirculation.

The bottom hole assembly 100 of the illustrated example includes alogging-while-drilling (LWD) module 120, one or moremeasuring-while-drilling (MWD) modules 130, a roto-steerable system anda motor, and the drill bit 105.

The example LWD module 120 is housed in a special type of drill collarand can contain one or a plurality of types of logging tools. It willalso be understood that more than one LWD and/or MWD module can beemployed, for example, as represented at 120A. References throughout toa module at the position of 120 can mean a module at the position of120A as well. The LWD module 120 includes capabilities for measuring(e.g., information acquiring devices), processing, and storinginformation (e.g., an information storage device such as, for example,nonvolatile memory), as well as for communicating with the surfaceequipment such as for example, a logging and control unit 160.

The example MWD module 130 is also housed in a special type of drillcollar and can contain one or more devices for measuring characteristicsof the drill string 12 and the drill bit 105. The MWD tool furtherincludes an apparatus (not shown) for generating electrical power to thedownhole system. This may include a mud turbine generator powered by theflow of the drilling fluid 26 and/or other power and/or battery systems.In some examples, the MWD module includes one or more of the followingtypes of measuring devices: a weight-on-bit measuring device, a torquemeasuring device, a vibration measuring device, a shock measuringdevice, a stick slip measuring device, a direction measuring device, andan inclination measuring device.

FIG. 2 is a schematic of an example drill bit assembly 200 disclosedherein, which may be used to implement the example LWD tool 120 ofFIG. 1. The example drill bit assembly 200 of FIG. 2 includes a drillbit 202 and an extension 204. In the illustrated example, the extension204 operatively couples the drill bit 202 to a downhole tool 206 suchas, for example, the measuring-while-drilling (MWD) tool 130 of FIG. 1.The example drill bit assembly 200 may be used to drill a boreholeand/or penetrate a subterranean formation. For example, a motor (notshown) operatively coupled to the drill bit assembly 200 may drive thedrill bit 202 via a drive shaft (not shown). In some examples, drillingfluid is flowed into the borehole to lubricate the drill bit 202 and/orcarry formation cuttings, debris, and/or fluid toward a surface ofEarth. In some examples, the drilling fluid is flowed through thedownhole tool 206 and exits the drill bit 202 via ports 208, 210. Inother examples, the drilling fluid is flowed through the downhole tool206 and exits the downhole tool 206 via a drive shaft channel (notshown) disposed uphole of the drill bit assembly 200. In other examples,the drilling fluid is flowed into the borehole in other ways. In someexamples, the downhole tool 206 and/or the drill bit assembly 202 ofFIG. 2 is operated in a way described in U.S. Pat. No. 6,057,784,entitled “Apparatus and System for Making At-Bit Measurements WhileDrilling,” filed Sep. 2, 1997, which is hereby incorporated by referenceherein in its entirety.

During drilling, one or more drilling events may occur. For example, thedrill bit 202 may penetrate a gas zone, the drill bit 202 may penetratea layer of a subterranean formation, the drill bit 202 may move past afirst portion of a subterranean formation having a first geologicalproperty to a second portion of the subterranean formation having asecond geological property, a component of the drill bit assembly 200may operate (e.g., a valve may open or close, a turbine may rotate, ashaft may rotate, etc.) and/or one or more other drilling events orcombinations of events may occur.

The example drill bit assembly 200 of FIG. 2 includes an example imagingsystem 211 to detect and/or monitor drilling events. In the illustratedexample, the imaging system 211 includes an example image conduit 212,an example image sensor 214, an example image processor 216, and anexample first transceiver 218. The example first transceiver 218includes a transmitter and a receiver. In the illustrated example, theimage conduit 212 substantially extends from an end or tip 220 of thedrill bit 202 through the drill bit 202 and into the extension 204. Inother examples, the image conduit 212 is disposed in and/or extendsbetween other portions of the example drill bit assembly 200. Further,other examples include other numbers of image conduits (e.g., 2, 3, 4,etc.). Moreover, while the example image conduit 212 of FIG. 2 issubstantially straight, the drill bit assembly 200 is implemented inother examples using one or more curved image conduits.

The example image conduit 212 of FIG. 2 is a fiber optic image conduit.In other examples, other image conduits such as, for example, lenses,filters, mirrors, and/or other image conduits are employed. A first end222 of the example image conduit 212 of FIG. 2 is in opticalcommunication with (e.g., has an optical field-of-view that includes) atarget adjacent the tip 220 of the drill bit 202. In the illustratedexample, the target may be formation fluid, cuttings, one or morebubbles, debris, a portion of a subterranean formation, and/or any othertarget. In some examples, an optical window is disposed between thefirst end 222 of the image conduit 212 and the target. In some examples,the optical window is a sapphire window. In some examples, the opticalwindow isolates, insulates and/or protects the image conduit 212 fromdrilling fluid, debris, cuttings, formation fluid, downhole conditions(e.g., high temperatures and/or pressures), etc. In some examples, theoptical window includes a coating to protect the optical window and/orrepel oil, water and/or other fluids and/or debris. In other examples,the first end 222 of the image conduit 212 is in contact with thetarget. For example, the first end 222 may be in contact with formationfluid flowing in the borehole. In some examples, the first end 222includes a coating to protect the first end 222 and/or repel oil, water,and/or other fluids and/or debris from the first end 222.

In the illustrated example, a second end 224 of the image conduit 212 isin optical communication with the image sensor 214. The example imageconduit 212 conveys or directs light conveying images from the first end222 of the image conduit 212 to the image sensor 214 via the second end224. The example image sensor 214 captures the images at a high framerate. For example, the image sensor 214 may capture the images at aframe rate of about 1000 frames per second. In other examples, the imagesensor 214 captures the images at other frame rates. In some examples,the image sensor 214 is a video camera.

In some examples, flushing fluid is flowed through the ports 208, 210 toproject the flushing fluid into a field-of-view of the image sensor 214.For example, the flushing fluid may be projected into an area of aborehole adjacent the drill bit assembly 200 such as, for example, atand/or near the first end 222 of the image conduit 212. In someexamples, the flushing fluid is a clear or substantially transparentliquid or gel. Thus, by projecting the flushing fluid into thefield-of-view of the image sensor 214, the field-of-view of the imagesensor 214 is flushed of obstructions between the image sensor 214 andthe target such as, for example, opaque fluids, debris, and/or otherobstructions. As a result, the example image sensor 214 has anunobstructed field-of-view that includes the target. The exampleflushing fluid may also clean the target and/or the first end 222 of theimage conduit 212. In some examples, the flushing fluid is flowedthrough the ports 208, 210 periodically or momentarily such as, forexample, during a time when the image sensor 214 is capturing images. Insome examples, the example drill bit assembly 200 uses flushing fluid asdescribed in U.S. application Ser. No. 13/439,824, filed on Apr. 4,2012, which is hereby incorporated by reference herein in its entirety.

During drilling, the drill bit assembly 200 moves relative to targetscaptured in the images. For example, if the target is a bubble, thebubble may flow past the first end 222 of the image conduit 212 and/orthe drill bit assembly 200 may be rotating and/or vibrating as theimages are captured. The example image processor 216 processes theimages to increase a signal-to-noise ratio of the image sensor 214and/or reduce, and/or minimize an effect of motion parallax such asblurring of the images. In the illustrated example, the image processor216 combines images to generate a processed image having less orsubstantially no blur relative to the images captured by the imagesensor 214. In some examples, the image processor 216 performs motionand/or depth estimation of the target to generate the processed image.An example image processing technique which may be implemented by theexample image processor 216 of FIG. 2 is described in Komuro et al.,High-S/N Imaging of a Moving Object using a High-frame-rate Camera, 2008IEEE International Conference on Image Processing (ICIP 2008) (SanDiego, Oct. 13, 2008), pp. 517-520, which is hereby incorporated byreference herein in its entirety.

For example, noise of the image sensor 214 may include fixed-patternnoise, random noise, shot noise and/or quantization noise. Assuming thatquantization noise is negligible and/or is included in random noiseand/or shot noise, a luminance value L(x, y, t) at pixel (x, y) of theimage sensor 214 in frame t may be presented by Equation 1 below:L(x,y,t)=aI(x,y,t)T _(c)+n _(f)(x,y)+n _(r)(x,y,t),  (1)In equation 1, I(x, y, t) is a light intensity incident on the pixel (x,y) in frame t, T_(e) is an exposure time, n_(f) is fixed pattern noiseand n_(r) is random noise in the combined image. If luminance does notvary after movement, a relationship can be written as shown in Equation2:I(u(x,y,t),v(x,y,t),t)=I(x,y,t ₀).  (2)A combined image of F frames {circumflex over (L)}(x, y) is given byEquations 3-4:

⁢L . ⁡ ( x , y ) = ⁢ 1 F ⁢ ∑ t = t 0 t 0 + F ⁢ L ⁡ ( u , v , t ) = ⁢ α ⁢ ⁢ I ⁡ ( x, y , t 0 ) ⁢ T + ⁢ 1 F ⁢ ∑ t = t 0 + F ⁢ ( n f ⁡ ( u , v ) + n r ⁡ ( u , v ,t ) ) . ( 3 ) ( 4 )If an average of each of the fixed-pattern noise, random noise, shotnoise and/or quantization noise is zero, a variance of random noise inthe combined image is reduced to 1/F by combining images. Fixed-patternnoise may be minimized by preprocessing and/or is reduced in proportionto a reciprocal of a square root of a number of pixels a target movesthrough.

If the target is a single plane, movement of the target may be estimatedby feature point tracking and/or template matching. If the target is athree dimensional object, a motion map and a depth map may be determinedsubstantially simultaneously. If initial values of the depth map aregiven, iteration processing may be used to estimate the motion and thedepth map of the target alternately via estimation by template matching.In some examples, estimation of motion p(t) of the target and the depthmap Z(x, y) is determined in terms of an optimization problem thatminimizes the following equation:

⁢J = ∑ t ⁢ ∑ x , y ⁢ ( 1 F ⁢ ∑ ⁢ L ⁡ ( u , v , t ′ ) - L ⁡ ( u , v , t ) ) 2 .( 5 )If the target is assumed to be rigid, the motion of the target isexpressed by the following parameters, including three rotation anglesand three translational distances:

$\begin{matrix}{{p(t)} = {\left( {{\theta_{x}(t)},{\theta_{y}(t)},{\theta_{z}(t)},{t_{x}(t)},{t_{y}(t)},{t_{z}(t)}} \right).}} & (6)\end{matrix}$If p(t₀)=0 in a first frame, a three dimensional position (X, Y, Z) ofimage coordinates (x, y) satisfies the following equations:X(x,y)=xZ(x,y)/f  (7)Y(x,y)=yZ(x,y)/f  (8)In Equations 7 and 8, f is a focal length. Using Equations 7 and 8,image coordinates u(x, y, t), v(x, y, t) in frame t corresponding toimage coordinates (x, y) in the first frame are determined as follows:

u ⁡ ( x , y ; p ⁡ ( t ) , Z ⁡ ( x , y ) ) = f ⁢ ⁢ ( r 11 ⁡ ( t ) ⁢ x / f + r 12⁡( t ) ⁢ y / f + r 13 ⁡ ( t ) ) ⁢ Z ⁡ ( x , y ) + t ⁡ ( t ) ( r 31 ⁡ ( t ) ⁢ x /f + r 32 ⁡ ( t ) ⁢ y / f + r 33 ⁡ ( t ) ) ⁢ Z ⁡ ( x , y ) + t ⁡ ( t ) ( 9 ) v ⁡( x , y ; p ⁡ ( t ) , Z ⁡ ( x , y ) ) = f ⁢ ⁢ ( r 21 ⁡ ( t ) ⁢ x / f + r 22 ⁡ (t ) ⁢ y / f + r 23 ⁡ ( t ) ) ⁢ Z ⁡ ( x , y ) + t y ⁡ ( t ) ( r 31 ⁡ ( t ) ⁢ x /f + r 32 ⁡ ( t ) ⁢ y / f + r 33 ⁡ ( t ) ) ⁢ Z ⁡ ( x , y ) + t ⁡ ( t ) , ( 10 )In Equations 9 and 10, r_(ij) are elements of a rotation matrix derivedfrom θ_(x), θ_(y), θ_(z). The following algorithm flow is then used:

1) Initialize the following variables:L(x,y)=L(x,y,1),Z(x,y)=Z ₀,

2) Obtain p(t) that minimizes the following equation:

$\begin{matrix}{J = {\sum\limits_{t}{\sum\limits_{x,y}{\left( {{\hat{L}\left( {x,y} \right)} - {L\left( {u,v,t} \right)}} \right)^{2}.}}}} & (11)\end{matrix}$

3) Obtain Z(x, y) that minimizes Equation 5;

4) Update {circumflex over (L)}(x, y) using the following equation:

⁢L ^ ⁡ ( x , y ) = 1 F ⁢ ∑ ⁢ L ⁡ ( u , v , t ) . ( 12 )

5) Iterate 2)-4) of the algorithm flow a plurality of times.

For motion estimation, p(t) that minimizes J in Equation 11 is equal top(t) that minimizes Equation 13 below because p(t) is involved in apartial sum for the frame t in Equation 11.

$\begin{matrix}{J_{t} = {\sum\limits_{x,y}{\left( {{\hat{L}\left( {x,y} \right)} - {L\left( {u,v,t} \right)}} \right)^{2}.}}} & (13)\end{matrix}$In some examples, a solution to Equation 13 is determined using aniterative calculation shown in Equations 14-18 below in which aLucas-Kanade method is applied to a perspective projection model.

$\begin{matrix}{{p^{({k + t})}(t)} = {{p^{(k)}(t)} + {\Delta\;{p^{(k)}(t)}}}} & (14) \\{{\Delta\;{p^{(k)}(t)}} = {\left( {\sum\limits_{x,y}{A^{T}A}} \right)^{- 1}{\sum\limits_{x,y}{Ab}}}} & (15) \\{A = {{\nabla{L\left( {x,y,t} \right)}}\frac{\partial{W\left( {x,{y;{p^{(k)}(t)}}} \right)}}{\partial p}}} & (16) \\{b = {{L\left( {x,y} \right)} - {L\left( {{W\left( {x,{y;{p^{(k)}(t)}}} \right)},t} \right)}}} & (17) \\{{W\left( {x,{y;{p(t)}}} \right)} = {\left( {{u\left( {x,{y;{p(t)}}} \right)},{v\left( {x,y,{p(t)}} \right)}} \right).}} & (18)\end{matrix}$

For depth estimation, Z(x, y) that minimizes J in Equation 5 is equal toZ(x, y) that minimizes Equation 19 below and can be calculated for each(x, y):

⁢J x , y = ∑ ⁢ ( 1 F ⁢ ∑ ⁢ L ⁡ ( u , v , t ′ ) - L ⁡ ( u , v , t ) ) 2 ( 19 )This is a one-dimensional search. By using information of a plurality offrames in this manner, the depth may be estimated. In some examples,J_(x,y) is smoothed via a Gaussian filter before searching for Z(x, y)that minimizes J_(x,y). In some examples, the depth map is smoothed foreach iteration.

The example image processor 216 of FIG. 2 determines target informationbased on the sensed images and/or the processed image(s). In someexamples, the image processor 216 determines target information such as,for example, object boundary information, a trajectory of the target, ashape of the target, a number of targets in the images and/or theprocessed image(s), a color of the target, a texture of the target,and/or other target information. In some examples, the image processor216 is used to implement image-based downhole fluid analysis such as,for example, the image-based downhole fluid analysis implemented in U.S.Pat. No. 8,483,445, filed on Sep. 26, 2011, which is hereby incorporatedby reference herein in its entirety.

In some examples, the image processor 216 analyzes and/or processes thetarget information to determine and/or detect a drilling event such as,for example, penetration of a gas zone, penetration of a layer of asubterranean formation, a change in a geological property of asubterranean formation through which the drill bit 202 is drilling,and/or any other drilling event. In some examples, the image processor216 generates drilling information including a determination of thedrilling event based on the target information. The example imageprocessor 216 can, for example, compress, encrypt, modulate and/orfilter the target information and/or the drilling information to formatthe target information and/or the drilling information. In someexamples, formatted target information and/or formatted drillinginformation is communicated from the drill bit assembly 200 via thefirst transceiver 218 to a second transceiver 226 of the downhole tool206, and the formatted target information and/or the formatted drillinginformation is reported via a telemetry link 228 toward a surface ofEarth. The example telemetry link 228 may be a modem or a low bandwidthtelemetry link such as, for example, a mud-pulse telemetry link. Becausethe example image processor 216 processes the images downhole todetermine the target information and/or the drilling information, whichcan include less data than the original image, the target informationand/or the drilling information is communicated uphole to the surface ofEarth via the telemetry link 228 in real-time. As a result, the exampleimaging system 211 enables an operator of the example downhole tool 206to quickly and timely respond to the event. For example, based on thedrilling information, the operator may adjust a speed of rotation of thedrill bit 202, a trajectory of the drill bit 202, etc.

In the illustrated example, the first transceiver 218 and the secondtransceiver 226 enable communication between the example drill bitassembly 200 and the example downhole tool 206. Thus, information may becommunicated from the downhole tool 206 to the drill bit assembly 200.In some examples, information from the surface is communicated to thedrill bit assembly 200 in real time via the telemetry link 228, thesecond transceiver 226 and the first transceiver 218.

FIG. 3 illustrates the example drill bit assembly 200 of FIG. 2 havingthe image conduit 212 extending from inside the extension 204 to a side300 of the extension 204. Thus, the example image conduit 212 of FIG. 3may be used to capture images of targets adjacent the extension 204 suchas, for example, a penetrated portion of a subterranean formation,formation fluid, cuttings, drilling fluid and/or any other target.

FIG. 4 is a schematic of the example downhole tool 206 including anexample drill bit assembly 400 having another example imaging system 401disclosed herein. The example drill bit assembly 400 of FIG. 4 includesa drill bit 402 and an extension 404. In the illustrated example, theimaging system 401 includes a first example image conduit 406, a secondexample image conduit 408 and a third example image conduit 410. Otherexamples have other numbers of image conduits. In the illustratedexample, the first image conduit 406 extends from the extension 404 toan end or tip 412 of the drill bit 402. The example second image conduit408 is disposed in the extension 404 and extends to a first side 414 ofthe extension 404. The example third image conduit 410 is disposed inthe extension 404 and extends to a second side 416 of the extension 404.

In the illustrated example, each of the first image conduit 406, thesecond image conduit 408 and the third image conduit 410 includes anexample imaging fiber bundle 417 and an example illumination fiberbundle 418. The example imaging fiber bundles 417 enable images to beconveyed along lengths of the respective image conduits 406, 408, 410.The example illumination fiber bundles 418 are disposed adjacent theimaging fiber bundles 417. In some examples, the illumination fiberbundles 418 substantially surround the imaging fiber bundles 417. In theillustrated example, the illumination fiber bundles 418 convey lightgenerated from a light source 419 to, for example, illuminate areasadjacent the drill bit assembly 400.

In the illustrated example, each of the first image conduit 406, thesecond image conduit 408 and the third image conduit 410 direct theimages to an example hemispherical mirror 420 disposed in the extension404. The example hemispherical mirror 420 of FIG. 4 reflects the imagesto an example image sensor 421 via a lens 422 disposed between thehemispherical mirror 420 and the image sensor 421. Thus, in theillustrated example, the example image sensor 421 captures images oftargets disposed in a plurality of positions or areas relative to thedrill bit assembly 400 via the first image conduit 406, the second imageconduit 408 and the third image conduit 410. In the illustrated example,the image sensor 421 captures the images at a high frame rate.

The example drill bit assembly 400 of FIG. 4 includes an example imageprocessor 424 to process and/or analyze the images captured by theexample image sensor 421. In some examples, the image processor 424processes the images to increase a signal-to-noise ratio of the imagesensor 421 and/or reduce, and/or minimize an effect of motion parallaxsuch as blurring of the images. In the illustrated example, the imageprocessor 424 combines images of each the targets to generate processedimages having less or substantially no blur relative to the imagescaptured by the image sensor 421. In some examples, the image processor424 performs motion and/or depth estimation of the target to generatethe processed image. An example image processing technique which may beimplemented by the example image processor 424 of FIG. 4 is described inKomuro et al., High-S/N Imaging of a Moving Object using aHigh-frame-rate Camera, 2008 IEEE International Conference on ImageProcessing (ICIP 2008) (San Diego, Oct. 13, 2008), pp. 517-520, which isdiscussed above.

The example image processor 424 of FIG. 4 determines target informationbased on the sensed images and/or the processed image(s). In someexamples, the image processor 424 determines object boundaryinformation, trajectories of the targets, target shapes, numbers oftargets, colors of the targets, textures of the targets, and/or othertarget information. In some examples, the image processor 424 determinestarget information by implementing image-based downhole fluid analysissuch as, for example, the image-based downhole fluid analysis describedin U.S. Pat. No. 8,483,445, filed on Sep. 26, 2011. For example, basedon the images, the image processor 424 may characterize and/or identifyformation fluids, quantify an amount of oil and/or water included in theformation fluids, and/or conduct other types of downhole fluid analyses.Other downhole fluid analysis techniques which may be implemented usingthe example image processor 424 are described in U.S. Publication No.2007/0035736, filed on Aug. 15, 2005; U.S. Pat. No. 5,663,559, filedJun. 7, 1995; U.S. Pat. No. 7,675,029, filed Aug. 26, 2004; and U.S.Pat. No. 5,410,391, filed Jun. 15, 1990. U.S. Publication No.2007/0035736, U.S. Pat. No. 5,663,559, U.S. Pat. No. 7,675,029, and U.S.Pat. No. 5,410,391 are hereby incorporated herein by reference in theirentireties.

In some examples, the image processor 424 analyzes and/or processes thetarget information to determine and/or detect a drilling event such as,for example, penetration of a gas zone, penetration of a layer of asubterranean formation, a change in a geological property of asubterranean formation through which the drill bit 402 is drilling,and/or any other drilling event. In some examples, if a drilling eventis detected, the image processor 424 generates drilling informationbased on the target information. In some examples, the example imageprocessor 424 formats the target information and/or the drillinginformation by compressing, encrypting, modulating and/or filtering thetarget information and/or the drilling information.

The target information and/or the drilling information is communicatedfrom the example drill bit assembly 400 via a wireless transmitter 426to the second transceiver 226 of the example downhole tool 206. In someexamples, the wireless transmitter 426 is included in a transceiverdisposed on the drill bit assembly 400. In the illustrated example, thetarget information and/or the drilling information is communicated fromthe downhole tool 206 toward a surface of earth via the telemetry link228. In some examples, the telemetry link 228 implements a low bandwidthtelemetry link such as, for example, a mud-pulse telemetry link. Byprocessing the target information and/or the drilling informationdownhole in the example drill bit assembly 400, the target informationmay be communicated from example drill bit assembly 400 to the surfaceof Earth in real-time. As a result, an operator of the example drill bitassembly 400 may respond to the drilling information and/or the targetinformation by, for example, by adjusting an operating parameter of thedrill bit assembly 400 such as, for example, a speed of rotation of thedrill bit 402, an angle of trajectory of the drill bit 402, etc.

In some examples, flushing fluid is flowed through ports 428, 430 toproject the flushing fluid into a field-of-view of the image sensor 421.In some examples, the flushing fluid flushes away obstructions and/orcleans the targets, the first image conduit 406, the second imageconduit 408 and/or the third image conduit 410. In some examples, theexample drill bit assembly 400 implements techniques involving flushingfluid that are described in U.S. application Ser. No. 13/439,824, filedon Apr. 4, 2012.

FIG. 5 is a schematic of the example downhole tool 206 having anotherexample drill bit assembly 500 disclosed herein. In the illustratedexample, the drill bit assembly 500 includes a drill bit 502 and anextension 504. The example drill bit assembly 500 of FIG. 5 includes anexample imaging system 506 that is used to detect and/or determinedrilling information such as, for example, movement, a position and/or acondition of one or more components of the example drill bit assembly500. In the illustrated example, the imaging system 506 is used tomonitor a valve 508 operatively coupled to a shaft 510 disposed in theexample extension 504. For example, the imaging system 506 may be usedto detect a position of the valve 508, a state of wear and/or acondition of one or more components of the valve, and/or otherinformation. Although the following examples are described inconjunction with the example valve 508 of FIG. 5, in other examples, theimaging system 506 is used to detect and/or monitor other components ofthe drill bit assembly 500.

The example imaging system 506 includes an image conduit 512 disposedbetween the valve 508 and an example image sensor 513. In theillustrated example, the image conduit 512 includes an example imagingfiber bundle 514 and an example illumination fiber bundle 516. Theexample illumination fiber bundle 516 is illuminated via an examplelight source 518 to illuminate a field of view including at least aportion of the example valve 508. In the illustrated example, theimaging fiber bundle 514 directs light conveyed images of the examplevalve 508 to the image sensor 513 via a lens 520.

The example imaging system 506 of FIG. 5 includes an example imageprocessor 522 to process and/or analyze the images captured by theexample image sensor 513. In some examples, the image processor 522processes the images to increase a signal-to-noise ratio of the imagesensor 513 and/or reduce and/or minimize an effect of motion parallaxsuch as blurring of the images. For example, rotation of the valve 508may cause an image of the valve 508 captured by the image sensor 513 tobe blurred. In the illustrated example, the image processor 522 combinesimages to generate a processed image having less or substantially noblur relative to the images captured by the image sensor 513. In someexamples, the image processor 522 performs motion and/or depthestimation of a target in the image (e.g., a portion of the valve 508)to generate the processed image. An example image processing techniquewhich may be implemented by the example image processor 522 of FIG. 5 isdescribed in Komuro et al., High-S/N Imaging of a Moving Object using aHigh-frame-rate Camera, 2008 IEEE International Conference on ImageProcessing (ICIP 2008) (San Diego, Oct. 13, 2008), pp. 517-520, which isdiscussed above.

The example image processor 522 of FIG. 5 determines target informationbased on the sensed images and/or the processed image(s). For example,the image processor 522 determines object boundary information, a shapeof a target, a color of the target, a texture of the target, and/orother target information. In some examples, based on the targetinformation, the image processor 522 determines drilling informationsuch as, for example, movement of the valve 508, a position of the valve508, a state of the valve (e.g., open or closed, operating, etc.), acondition of one or more components of the valve 508, and/or otherdrilling information. In some examples, the example image processor 522formats the target information and/or the drilling information bycompressing, encrypting, modulating and/or filtering the targetinformation and/or the drilling information.

The target information and/or the drilling information is communicatedto the example downhole tool 206 via a wireless transmitter 524. Thetarget information and/or the drilling information is received by thesecond transceiver 226 and communicated to a surface of Earth via thetelemetry link 228. In some examples, the telemetry link 228 is a lowbandwidth telemetry link such as, for example, a mud-pulse telemetrylink. By processing the target information and/or the drillinginformation downhole in the example drill bit assembly 500, the targetinformation and/or the drilling information may be communicated to thesurface of Earth in real-time. As a result, an operator of the exampledrill bit assembly 500 may determine if the example valve 508 isoperating properly, if a component of the valve 508 is worn, etc.

FIG. 6 is a schematic of an example image conduit 600 disclosed herein,which may be used to implement the example image conduit 212 of FIGS.2-3, the example first image conduit 406 of FIG. 4, the example secondimage conduit 408 of FIG. 4, the example third image conduit 410 of FIG.4, and/or the example image conduit 512 of FIG. 5. In the illustratedexample, the image conduit 600 includes an example imaging fiber bundle602 having a plurality of imaging fibers 604. The example imaging fibers604 convey images from a first end 606 to a second end 608 of theexample image conduit 600.

The example image conduit 600 also includes an example illuminationfiber bundle 610 having a plurality of illumination fibers 612. Light isconveyed to a field-of-view via the example illumination fibers 612. Inthe illustrated example, the illumination fibers 612 are disposedadjacent the imaging fiber bundle 602. In some examples, theillumination fibers 612 substantially surround the imaging fiber bundle602. In some examples, the image conduit 600 is flexible and may be bentor curved during operation. In other examples, the image conduit 600 isrigid and/or substantially straight. Other example image conduits whichmay be used to implement the examples disclosed herein are described inU.S. patent application Ser. No. 13/654,408, filed on Oct. 17, 2012,which is hereby incorporated by reference herein in its entirety.

While example manners of implementing the example imaging system 211,the example imaging system 401, and the example imaging system 506 areillustrated in FIGS. 2-5, one or more of the elements, processes and/ordevices illustrated in FIGS. 2-5 may be combined, divided, re-arranged,omitted, and/or implemented in any other way. Further, the example imagesensor 214, the example image processor 216, the example firsttransceiver 218, the example second transceiver 226, the exampletelemetry link 228, the example light source 419, the example imagesensor 421, the example image processor 424, the example transmitter426, the example image sensor 513, the example light source 518, theexample image processor 522, the example transmitter 524 and/or, moregenerally, the example imaging system 211 of FIGS. 2 and 3, the exampleimaging system 401 of FIG. 4, and/or the example imaging system 506 ofFIG. 5 may be implemented by hardware, software, firmware and/or anycombination of hardware, software and/or firmware. Thus, for example,any of the example image sensor 214, the example image processor 216,the example first transceiver 218, the example second transceiver 226,the example telemetry link 228, the example light source 419, theexample image sensor 421, the example image processor 424, the exampletransmitter 426, the example image sensor 513, the example light source518, the example image processor 522, the example transmitter 524and/or, more generally, the example imaging system 211 of FIGS. 2 and 3,the example imaging system 401 of FIG. 4, and/or the example imagingsystem 506 of FIG. 5 could be implemented by one or more analog ordigital circuit(s), logic circuits, programmable processor(s),application specific integrated circuit(s) (ASIC(s)), programmable logicdevice(s) (PLD(s)) and/or field programmable logic device(s) (FPLD(s)).When reading any of the apparatus or system claims of this patent tocover a purely software and/or firmware implementation, at least one ofthe example image sensor 214, the example image processor 216, theexample first transceiver 218, the example second transceiver 226, theexample telemetry link 228, the example light source 419, the exampleimage sensor 421, the example image processor 424, the exampletransmitter 426, the example image sensor 513, the example light source518, the example image processor 522, the example transmitter 524and/or, more generally, the example imaging system 211 of FIGS. 2 and 3,the example imaging system 401 of FIG. 4, and/or the example imagingsystem 506 of FIG. 5 is/are hereby expressly defined to include atangible computer readable storage device or storage disk such as amemory, a digital versatile disk (DVD), a compact disk (CD), a Blu-raydisk, etc. storing the software and/or firmware. Further still, theexample imaging system 211 of FIGS. 2 and 3, the example imaging system401 of FIG. 4, and/or the example imaging system 506 of FIG. 5 mayinclude one or more elements, processes and/or devices in addition to,or instead of, those illustrated in FIGS. 2-5, and/or may include morethan one of any of the illustrated elements, processes and devices.

A flowchart representative of an example method that may be used toimplement the example image sensor 214, the example image processor 216,the example first transceiver 218, the example second transceiver 226,the example telemetry link 228, the example light source 419, theexample image sensor 421, the example image processor 424, the exampletransmitter 426, the example image sensor 513, the example light source518, the example image processor 522, the example transmitter 524, theexample imaging system 211 of FIGS. 2 and/or 3, the example imagingsystem 401 of FIG. 4, and/or the example imaging system 506 of FIG. 5 isshown in FIG. 7. The method may be implemented using machine readableinstructions that comprise a program for execution by a processor suchas the processor 812 shown in the example processor platform 800discussed below in connection with FIG. 8. The program may be embodiedin software stored on a tangible computer readable storage medium suchas a CD-ROM, a floppy disk, a hard drive, a digital versatile disk(DVD), a Blu-ray disk, or a memory associated with the processor 812,but the entire program and/or parts thereof could be executed by adevice other than the processor 812 and/or embodied in firmware ordedicated hardware. Further, although the example program is describedwith reference to the flowchart illustrated in FIG. 7, many othermethods of implementing the example image sensor 214, the example imageprocessor 216, the example first transceiver 218, the example secondtransceiver 226 the example telemetry link 228, the example light source419, the example image sensor 421, the example image processor 424, theexample transmitter 426, the example image sensor 513, the example lightsource 518, the example image processor 522, the example transmitter524, the example imaging system 211 of FIGS. 2 and/or 3, the exampleimaging system 401 of FIG. 4, and/or the example imaging system 506 ofFIG. 5 may be used. For example, the order of execution of the blocksmay be changed, and/or some of the blocks described may be changed,omitted, or combined.

As mentioned above, the example method of FIG. 7 may be implementedusing coded instructions (e.g., computer and/or machine readableinstructions) stored on a tangible computer readable storage medium suchas a hard disk drive, a flash memory, a read-only memory (ROM), acompact disk (CD), a digital versatile disk (DVD), a cache, arandom-access memory (RAM) and/or any other storage device or storagedisk in which information is stored for any duration (e.g., for extendedtime periods, permanently, for brief instances, for temporarilybuffering, and/or for caching of the information). As used herein, theterm tangible computer readable storage medium is expressly defined toinclude any type of computer readable storage device and/or storage diskand to exclude propagating signals. As used herein, “tangible computerreadable storage medium” and “tangible machine readable storage medium”are used interchangeably. The example method of FIG. 7 may beimplemented using coded instructions (e.g., computer and/or machinereadable instructions) stored on a non-transitory computer and/ormachine readable medium such as a hard disk drive, a flash memory, aread-only memory, a compact disk, a digital versatile disk, a cache, arandom-access memory and/or any other storage device or storage disk inwhich information is stored for any duration (e.g., for extended timeperiods, permanently, for brief instances, for temporarily buffering,and/or for caching of the information). As used herein, the termnon-transitory computer readable medium is expressly defined to includeany type of computer readable device or disk and to exclude propagatingsignals. As used herein, when the phrase “at least” is used as thetransition term in a preamble of a claim, it is open-ended in the samemanner as the term “comprising” is open ended.

The example method 700 of FIG. 7 begins at block 702 by directing lightconveying an image of a target through a portion of a drill bitassembly. For example, the image conduit 212 of FIG. 2 may direct lightconveying an image of a portion of a subterranean formation through thedrill bit 202. In some examples, the image conduit 512 directs lightconveying an image of a component of the drill bit assembly 500 througha portion of the drill bit 502 and/or the extension 504. At block 704,the image is captured via an image sensor disposed in the drill bitassembly. For example, the image sensor 214 may capture the image and/ora plurality of images of the subterranean formation at a high frame ratesuch as, for example, about 1000 frames per second. At block 706, theimage is processed via an image processor disposed in the drill bitassembly to generate a processed image. For example, the image processor216 may combine the image with a plurality of previously captured imagesto generate a processed image having less or substantially no blurrelative to the images captured by the image sensor 214, therebyincreasing a signal-to-noise ratio of the image sensor 214. In someexamples, the image processor 216 estimates motion and/or depth of thetarget based on the images captured by the image sensor 214 to generatethe processed image.

At block 708, target information is determined based on the processedimage. The target information may include, for example, a color of thesubterranean formation, a texture of the subterranean formation, and/orother information. In some examples, the target information includesobject boundary information, a trajectory of the target, a size of thetarget, a shape of the target, and/or other target information.

At block 710, drilling information is determined based on the targetinformation. In some examples, determining the drilling informationincludes detecting a drilling event. Example drilling events includepenetration of a gas zone by the drill bit, a change in a geologicalproperty of a subterranean formation, operation of a component of thedrill bit assembly, etc. In some examples, the drilling informationincludes, a condition of the target (e.g., worn, functioning properly,etc.), a position of the target, a state of the target (e.g., stationaryor moving, open or closed, etc.), and/or other drilling information. Insome examples, the drilling information includes a characterization ofone or more fluids.

At block 712, at least one of the target information or the drillinginformation, or both, is wirelessly communicated uphole toward a surfaceof Earth. By processing the images downhole, the target informationand/or the drilling information may be communicated to the surface ofEarth in real time via a low bandwidth transmitter such as, for example,a mud-pulse telemetry link. For example, the first transceiver 218 maycommunicate the target information and/or the drilling information tothe second transceiver 226 of the downhole tool 206. In some examples,the telemetry link 228 then communicates the target information and/orthe drilling information to the surface of Earth. An operator of thedrill bit assembly may then use the target information and/or thedrilling information to operate a downhole tool (e.g., the downhole tool206) including the drill bit assembly. The example method 700 thenreturns to block 702.

FIG. 8 is a block diagram of an example processor platform 800 capableof executing the example method 700 of FIG. 7 to implement the exampleimaging system 211 of FIGS. 2-3, the example imaging system 401 of FIG.4, and/or the example imaging system 501 if FIG. 5. The processorplatform 800 can be, for example, a controller, a special-purposecomputing device, a mobile device or any other type of computing device.

The processor platform 800 of the illustrated example includes aprocessor 812. The processor 812 of the illustrated example is hardware.For example, the processor 812 can be implemented by one or moreintegrated circuits, logic circuits, microprocessors or controllers fromany desired family or manufacturer.

The processor 812 of the illustrated example includes a local memory 813(e.g., a cache). The processor 812 of the illustrated example is incommunication with a main memory including a volatile memory 814 and anon-volatile memory 816 via a bus 818. The volatile memory 814 may beimplemented by Synchronous Dynamic Random Access Memory (SDRAM), DynamicRandom Access Memory (DRAM), RAMBUS Dynamic Random Access Memory (RDRAM)and/or any other type of random access memory device. The non-volatilememory 816 may be implemented by flash memory and/or any other desiredtype of memory device. Access to the main memory 814, 816 is controlledby a memory controller.

The processor platform 800 of the illustrated example also includes aninterface circuit 820. The interface circuit 820 may be implemented byany type of interface standard, such as an Ethernet interface, auniversal serial bus (USB), and/or a PCI express interface.

In the illustrated example, one or more input devices 822 are connectedto the interface circuit 820. The input device(s) 822 permit(s) a userto enter data and commands into the processor 812. The input device(s)can be implemented by, for example, an audio sensor, a microphone, acamera (still or video), a keyboard, a button, a mouse, a touchscreen, atrack-pad, a trackball, isopoint and/or a voice recognition system.

In some examples, one or more output devices 824 are also connected tothe interface circuit 820 of the illustrated example.

The interface circuit 820 of the illustrated example also includes acommunication device such as a transmitter, a receiver, a transceiver, amodem and/or network interface card to facilitate exchange of data withexternal machines (e.g., computing devices of any kind) via a network826 (e.g., an Ethernet connection, a digital subscriber line (DSL),coaxial cable, etc.).

The processor platform 800 of the illustrated example also includes oneor more mass storage devices 828 for storing software and/or data.Examples of such mass storage devices 828 include floppy disk drives,hard drive disks, compact disk drives, Blu-ray disk drives, RAIDsystems, and digital versatile disk (DVD) drives.

The coded instructions 832 to implement the method(s) of FIG. 7 may bestored in the mass storage device 828, in the volatile memory 814, inthe non-volatile memory 816, and/or on a removable tangible computerreadable storage medium such as a CD or DVD.

From the foregoing, it will be appreciated that the above disclosedmethods, apparatus and articles of manufacture enable real timecommunication of drilling information while drilling a borehole. Someexamples disclosed herein employ an imaging system having an imagesensor that captures images at a high frame rate. In some examples, theimages are processed downhole to reduce, minimize and/or alleviateeffects of motion parallax such as blurring. By employing imageprocessing, the examples disclosed herein determine diverse types ofdrilling information such as characteristics of a subterraneanformation, characterizations of downhole fluids, conditions and/orstates of components of a drill bit assembly, and/or other drillinginformation.

Although only a few example embodiments have been described in detailabove, those skilled in the art will readily appreciate that manymodifications are possible in the example embodiments without materiallydeparting from this disclosure. Accordingly, such modifications areintended to be included within the scope of this disclosure as definedin the following claims. In the claims, means-plus-function clauses areintended to cover the structures described herein as performing therecited function and not only structural equivalents, but alsoequivalent structures. Thus, although a nail and a screw may not bestructural equivalents in that a nail employs a cylindrical surface tosecure wooden parts together, whereas a screw employs a helical surface,in the environment of fastening wooden parts, a nail and a screw may beequivalent structures. It is the express intention of the applicant notto invoke 35 U.S.C. §112, paragraph 6 for any limitations of any of theclaims herein, except for those in which the claim expressly uses thewords ‘means for’ together with an associated function.

The Abstract at the end of this disclosure is provided to comply with 37C.F.R. §1.72(b) to allow the reader to quickly ascertain the nature ofthe technical disclosure. It is submitted with the understanding that itwill not be used to interpret or limit the scope or meaning of theclaims.

What is claimed is:
 1. An apparatus, comprising: a drill bit assembly;an image sensor disposed in the drill bit assembly; an image conduitdisposed in the drill bit assembly, wherein the image conduit comprisesa first portion for conveying images from an end of the image conduithaving a field-of-view to the image sensor and a second portion forconveying light to illuminate the field-of-view; and an image processordisposed in the drill bit assembly, the image processor to processilluminated images acquired by the image sensor wherein the imageprocessor combines a plurality of the illuminated images to reduce noiseand to iteratively optimize a system of equations for motion and thendepth of a target in the field-of-view to reduce motion parallax.
 2. Theapparatus of claim 1, further comprising a wireless transceiver disposedin the drill bit assembly to wirelessly communicate with a downhole tooloperatively coupled to the drill bit assembly.
 3. The apparatus of claim1, wherein the drill bit assembly comprises a port to project flushingfluid.
 4. The apparatus of claim 1, wherein the image sensor is a videocamera.
 5. The apparatus of claim 1, wherein the image conduit is todirect the from a drill bit end of the drill bit assembly to the imagesensor.
 6. The apparatus of claim 1, comprising a second image conduitis to direct a second image from a side of the drill bit assembly to theimage sensor.
 7. The apparatus of claim 1, wherein the second imageconduit is disposed between the image sensor and a component of thedrill bit assembly.
 8. A method, comprising: illuminating afield-of-view that comprises a target; directing illuminated images ofthe target through a portion of a drill bit assembly from a first end ofan image conduit in optical communication with the target locatedexternally of the drill bit assembly to a second end of the first imageconduit in optical communication with an image sensor disposed at aseparate location within the drill bit assembly; capturing theilluminated images via the image sensor disposed inside the drill bitassembly; and processing the captured images wherein the processingcomprises combining a plurality of the captured images to reduce noiseand to iteratively optimize a system of equations for motion and thendepth of a target in the field-of-view to reduce motion parallax.
 9. Themethod of claim 8, comprising detecting a drilling event based at leastin part on the motion and depth of the target.
 10. The method of claim8, further comprising wirelessly communicating the drilling informationfrom the drill bit assembly to a surface of Earth.
 11. The method ofclaim 8, further comprising flushing an area adjacent the drill bitassembly with flushing fluid.
 12. The method of claim 8, wherein theimages comprise at least one of formation fluid or a portion of asubterranean formation when a drill bit of the drill bit assembly is atleast one of rotating or vibrating.
 13. An apparatus, comprising: adrill bit assembly operatively coupled to a downhole tool, the drill bitassembly including a drill bit, an image conduit, a light source, animage sensor and an image processor, the image conduit extending throughthe drill bit to an end that comprises a field-of-view illuminated bythe light source, wherein the image sensor is to capture illuminatedimages of a target via the image conduit, and the image processor is tocombine a plurality of the images to reduce noise and to iterativelyoptimize a system of equations for motion and then depth of a target inthe field-of-view to reduce motion parallax.
 14. The apparatus of claim13, wherein the image sensor is to capture the illuminated images at aframe rate of about one thousand frames per second.